A new approach to selection and weighting of items in evaluative composite measurement scales

Evaluative composite measurement scales (CMS) are increasingly used in medicine to measure complex constructs in the absence of a reference criterion or ‘gold standard’. However, the level of measurement provided by these instruments has usually been given little attention. This paper explores the influence of the characteristics of the item set and weighting on the level of measurment of an evaluative CMS. The approach is illustrated with an application to the scoring system of the Nottingham Health Profile. Simulations are provided to indicate when the composite score of item responses, on an ordinal or pass—fail scale, could be considered to achieve the properties of an interval scale.     

Dopamine antagonists reduce spontaneous electrical activity in cultured mammalian neurons from ventral mesencephalon

Mammalian neurons from ventral mesencephalon (VM) were grown in primary dissociated cell (PDC) culture. These neurons are predominantly non-dopaminergic. Many of these non-dopaminergic neurons have dopamine agonist and antagonist binding sites. Intracellular recordings were obtained from these neurons. When bathed in phosphate-buffered saline (PBS) solution they generated action potentials spontaneously. However, in the presence of haloperidol dissolved in PBS solution, the percentage of neurons which generated action potentials spontaneously was reduced in a dose-dependent manner (1–10 μM). This response was also obtained with (+) butaclamol (1 μM) but not with (−) butaclamol (1 μM). This neuroleptic inhibition of spontaneously generated action potentials was specific for neurons in PDC cultures of VM since neurons in PDC cultures of spinal cord did not demonstrate this phenomenon.     

Comparison of DSM-III-R and childhood autism rating scale diagnoses of autism

The purpose of this study was to clarify the issue of whether DSM-III-R (American Psychological Association [APA], 1987) over-or underdiagnoses autism by comparing this diagnostic system to a well-established objective measure of diagnosis, the Childhood Autism Rating Scale (CARS). A secondary goal was to determine which of the 16 criteria are the best discriminators of autism. DSM-III-R, CARS, and clinical diagnoses of 138 consecutive admissions to a statewide program for the diagnosis and treatment of autistic and related communication-handicapped individuals (Division TEACCH in North Carolina) were compared. Results indicated a generally high degree of agreement on the diagnosis of autism using the three systems. Within this tratment-oriented program, the CARS and clinical ratings diagnosed a greater number of cases as autistic than did the DSM-III-R criteria, suggesting that DSM-III-R slightly underdiagnosed autism. The criteria that most strongly related to the diagnosis of autism regardless of the system were lack of awareness of others, abnormal social play, an impaired ability to make friends, abnormal nonverbal communication, stereotypic body movements, and restricted range of interests.     

Illness-induced hyperalgesia is mediated by spinal neuropeptides and excitatory amino acids

The spinal cord dorsal horn contains neural mechanisms which can greatly facilitate pain. We have recently shown that ‘illness’-inducing agents, such as intraperitoneally administered lipopolysaccharide (LPS; bacterial endotoxin), can produce prolonged hyperalgesia. This hyperalgesic state is mediated at the level of the spinal cord via activation of the NMDA-nitric oxide cascade. However, prolonged neuronal depolarization is required before such a cascade can occur. The present series of experiments were aimed at identifying spinal neurotransmitters which might be responsible for creating such a depolarized state. These studies show that LPS hyperalgesia is mediated at the level of the spinal cord by substance P, cholecystokinin and excitatory amino acids acting at non-NMDA sites. No apparent role for serotonin or kappa opiate receptors was found.